Docker 之间如何共享数据？

容器之间共享数据

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第一种方法是将共享数据放在 bind mount 中，然后将其 mount 到多个容器。还是以 httpd 为例，不过这次的场景复杂些，我们要创建由三个nginx容器组成的 web server 集群，它们使用相同的 html 文件，操作如下：

（1）将 /data/nginx/html/ mount 到三个nginx 容器.

[[email protected] ~]# cat /data/nginx/html/index.html 
share directory
[[email protected] ~]# docker run -itd --name=nginx1 -v /data/nginx/html:/usr/share/nginx/html -p 81:80 nginx
60bbbe1fca8e998d70291c03dafb209222315619cc34d129d0cf27c120bc8766
[[email protected] ~]# docker run -itd --name=nginx2 -v /data/nginx/html:/usr/share/nginx/html -p 82:80 nginx
8d0c42ab5e5283b4d5cbecede776d3eface0e26b0a64b67f35135f4255dd8537
[[email protected] ~]# docker run -itd --name=nginx3 -v /data/nginx/html:/usr/share/nginx/html -p 83:80 nginx
db94a6b3086c0adeee17cd66b7e622d38f57890d76b82a228b937fdb43de0e2d


[[email protected] ~]# docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                NAMES
db94a6b3086c        nginx               "/docker-entrypoint.…"   16 seconds ago      Up 14 seconds       0.0.0.0:83->80/tcp   nginx3
8d0c42ab5e52        nginx               "/docker-entrypoint.…"   25 seconds ago      Up 24 seconds       0.0.0.0:82->80/tcp   nginx2
60bbbe1fca8e        nginx               "/docker-entrypoint.…"   39 seconds ago      Up 38 seconds       0.0.0.0:81->80/tcp   nginx1

（2）查看当前主页内容。 

[[email protected] ~]# curl 192.168.179.99:81
share directory
[[email protected] ~]# curl 192.168.179.99:82
share directory
[[email protected] ~]# curl 192.168.179.99:83
share directory

（3）修改 volume 中的主页文件，再次查看并确认所有容器都使用了新的主页。

[[email protected] ~]# echo "share directory changed" > /data/nginx/html/index.html 
[[email protected] ~]# curl 192.168.179.99:81
share directory changed
[[email protected] ~]# curl 192.168.179.99:82
share directory changed
[[email protected] ~]# curl 192.168.179.99:83
share directory changed

另一种在容器之间共享数据的方式是使用 volume container